Roast peppercorns, cardamoms, cloves, cinnamon, poppy seeds, coriander seeds, cumin seeds and red chilies in a dry frying pan for a few minutes, until aromatic and grind to a fine powder. Fry green chilies and onions with a little ghee and grind them along with half cup coriander leaves, mint leaves and powdered spices, to a fine paste.
Heat ghee in a pan. Add mutton pieces and fry for a minute. Add methi leaves and salt and fry for three minutes. Pour the ground masala paste over the chops and fry for five minutes, adding just half a cup of water. Add curds and mix well. Just before covering the pan, add the tomato and potato pieces. Cook till mutton is done. Uncover the pan and add dry methi leaves. Simmer for few minutes. Serve hot with remaining coriander leaves.